The present invention relates to a method of lubricating working machinery, and more particularly, to a method of lubricating working machinery in which even if a sliding surface oil used for lubrication of working machinery intermingles with a metal working oil, no trouble results.
A variety of lubricating oils having different characteristics are used in working machinery depending on the application part and the purpose of use. When, however, these lubricating oils intermingle with each other, there is a danger of reduction in their lubricating characteristics and occurrence of a fatal problem. Thus such intermingling is absolutely necessary to avoid.
In many working machines, particularly a transfer machine, however, a sliding surface oil often intermingles with a metal working oil such as a cutting oil and a grinding oil. In this case, if the metal working oil is of the aqueous emulsion type, the following problems arise.
(1) The metal working oil loses its uniformity of lubricating properties. For this reason, its metal working performance varies and it becomes impossible to accomplish high accuracy metal working.
(2) Decomposition is accelerated, and the service life of the metal working liquid is seriously reduced.
The present inventors have made extensive investigations to overcome the above problems.
As a result, it has been found that if a lubricating oil having a specific formulation and a specific coefficient of dynamic friction is applied to a sliding surface of working machinery, and a dilution of the lubricating oil composition is applied to a metal working section of the working machinery, the above problems can be overcome. Based on these findings, the present invention has been accomplished.